Also, I would expect most of that stuff to be worth well over spot, just given the dates.

And he that hath lyberte ought to kepe hit wel / For nothyng is better than lyberte / For lyberte shold not be wel sold for alle the gold and syluer of all the world.-Caxton's edition of Aesop's Fables, 1484

Probably. And if it's like the stuff I see most often, the silver content can be rounded down from all the wear. But again, the numismatic value should outweigh it. And we all know I want the British three-half-pence. Right? Riiiiight?